Briquette of phosphate-rock material and method of making the same



-to set. The mix is ra hes pr; 21.1925.

JAMESEA IEAEE, or mourn: PLEASANT, TENNESSEE, 'Assrcnon 'ro THE INTERNA- TIoN L NEWYORK.

Nom'awing,

T allioh'o mit may c'bncem 7 ,Be' it known that 1, JAMES A. BARR, a citizen of the United States, and resident of Mount Pleasant, in the county of Maury and State of Tennessee, have invented certain new and useful Improvements in Briquettes of Phosphate-Rock Material and Methods of Making the Same,- of which the followinglis a specification.v

10 y inventioiirelatesto briquettes made of phosphate rock material which are particularly adapted "for use in blast furnace charges in the manufacture of, iron. The

use of phosphate rock has been proposed for increasing the phosphorus content of iron (for the purpose of; increasing its fluidity,)

by adding the phosphate .material to the charge in the blast furnace; Due to the fact that phosphate rock material .oftoday 2 largely exlsts as fines, a considerfibl euloss wi ll result by the material being carried out the stack unless it is properly briquetted. Attempts have been made to-briquette the V phosphate=material by the use of the ordinary binding materials, such as pitch,vetc., but these'have introduced so much foreign material into the briquette -as :to be uneco-. 'nomical. V

I have now discovered thatI may employ phosphoric acid as a binding material for the briquettes, that the acid phosphates formed themselves constitute "an excellent binding material, while atftli'e-same time the increase in the 5"P O content due to the addition of this acid, renders thebri uette' of unusual 'value. for the purpose speci ed. p 4 v The following is an illustrative example of my improvedmethod; A Y A v One hundred parts by 'weight,gof phosphate sand runnin in size from i inch grains down to the'finest grains ordinarily obtained from commercial recovery systems are mixed 'witheight parts, by weight,-of waten- The moist? mixture of phosphate Q sand is then thoroughlymixed 'with; five l parts, by weight, of crude phosp ture of ,100' F. Ifthe mixing is continued too long-the material will dry out andstart .then passed {through .bri'quettmg. machinery of .standard' typ 1 AGRICULTURAL CORPORATION, OF-NEW YORK, N.

taking advantage of the fact oricacid I claim: er cent H PO;)'."' The mi ing with the p osphoric acid should take from one to" 50 three. minutes. andishould atja. tempera-- I -contammg an excess original material; I i :1] 2; fA briquetteof phosphate rock material,

Y., A CORPORATION OF BEI QUETTE 0E PHOSPHATE-ROCK MATERIAL AND METHOD or MAKINGTHE SAME.

.Application filcd'ltlarch 19, 1924. Serial in). 700,189.

such as the so-called Belgian roll machinery, and subjected to a pressure of about 8000, pounds to the square inch.. For the purpose of drying are discharged 'onto a slow .moving conveyor and maintained in an atmosphere heated to about 212 F., or thereabouts. The briquettes are kept i'nthis atmosphere until the hardening is completed, which usually takes place in a couple of hours. Conveniently, the

a slow moving conveyor and passed through a'drying chamber at such a rate that hard-f ening will becompleted when the chamberi has been traversed.

The chemical reaction is limited to the enough phossurface bf the grains since only phoric acid is added to artially convert the tricalcium phosphate to monoor dicalcium phosphate. The presence 0f the acid salts or salt thus 7 ing or set to take. place and, aided by the pressure-employed in the briquetting causes the material to assume a structure of the requisite hardness and coherence. The following is believed to represent the chemical reaction involved: I t as( 4)2+ s 4+ 2 f- L Ca, (POJri-Ca (H PO 2 .ZOaHPO "While phosphoric acidv of any origin may be used, I prefer to use the crude acid as produced by the commercial phosphate rocksulphuric acid process, as the acid thus produced usually contains impurities such as monocalcium phosphate, aluminum. phosphate etc.

which aid its binding action. If for any reason it may be desirable, small quantities materials maybe incorporated althou h, ordinarily, their presence is net requireg It Will vbe understood that the above example is by way of illustration only and that the details may, be widely varied without departing from the spirit ofmy invention.

1;, A briquette f phosphate rock material the particles of whi6h are held together by briquettes maybe discharged onto formed in situ causes an hardenbriquettes formed they I of the common organic binding acid calcium phosphate formed in situ and B 0; content over the the particles of held together by acid calcium phosphate formed by the reaction of said material with phosphoric acid.

3. A briquette of phosphate rock material comprising acid calcium phosphate and aluminum phosphates as binders.

4. The method which phosphate rock material with phosphoric acid' and briquetting the mixture before the reaction of said acid upon the material is completed.

5. The method which consists in mixing phosphate rock material with phosphoric acid, briquetting the mixture before the reaction of said acid upon the material is completed, and drying the briquettes so formed.

consists in mixingmanufacture,

6. The method which consists in mixing, finely divided rock material with phosphoric acid sufficientonly to react with the surface of the grains and briquetting the mixture before the reaction. of said acid upon the material is completed.

7. The method which consists in mixing phosphate rock material with crude phosphoric acid of phosphate rock-sulphuric acid briquetting the mixture before the reaction of said acid upon the material is completed, and drying the briquettes so formed.

JAMES A. BARR. 

